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Convert figure images to markdown

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James Gregory 2013-12-31 07:56:10 +11:00
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04-08.md
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@ -48,8 +48,7 @@ that the whole point of the wait state mechanism is to allow a device to
stretch out any access to itself for however much time it needs to
perform the access.
![](images/04-06.jpg)\
**Figure 4.6**  *Video wait states inserted by the display adapter.*
![**Figure 4.6**  *Video wait states inserted by the display adapter.*](images/04-06.jpg)
As with DRAM refresh, wait states don't stop the 8088 completely. The
Execution Unit can continue processing while wait states are inserted,
@ -101,8 +100,7 @@ leaving as little as about 10 percent of all display memory accesses for
the 8088. (These percentages vary considerably among the many EGA and
VGA clones.)
![](images/04-07.jpg)\
**Figure 4.7**  *Allocation of display memory access.*
![**Figure 4.7**  *Allocation of display memory access.*](images/04-07.jpg)
Second, because the displayed dots (or *pixels,* short for "picture
elements") must be drawn on the screen at a constant speed, many display
@ -121,8 +119,7 @@ access just as it becomes available, again as shown in Figure 4.8. Any
or all of the three factors I've described can result in wait states,
slowing the 8088 and creating the display adapter cycle.
![](images/04-08.jpg)\
**Figure 4.8**  *Display memory access slots.*
![**Figure 4.8**  *Display memory access slots.*](images/04-08.jpg)
If some of this is Greek to you, don't worry. The important point is
that display memory is not very fast compared to normal system memory.